For every bucket of predicted probability, what did the model actually hit? A well-calibrated model has actual win rate ≈ predicted prob. A negative gap means the model is overconfident in that bucket (dangerous); positive gap means it's underpredicting (safe). Rows turn red when |gap| > 5pp AND N ≥ 10.
Combined "all sports" is rarely meaningful — sports differ in market efficiency, signal availability, and base rates. Use the chips to drill into a single sport. N<50 (red) means the calibration is brittle; N≥200 (green) is trustworthy.
Filter: window=90d · sport=nfl_preseason
| Predicted-prob bucket | N | Mean predicted | Actual win rate | Gap (actual − predicted) | Brier |
|---|---|---|---|---|---|
| <50% | 7 | 49.6% | 42.9% | -6.7pp | 0.251 |
| 50-55% | 28 | 52.5% | 64.3% | +11.8pp | 0.247 |
| 55-60% | 19 | 57.3% | 52.6% | -4.7pp | 0.250 |
| 60-65% | 8 | 61.5% | 62.5% | +1.0pp | 0.242 |
| 70-75% | 3 | 73.4% | 66.7% | -6.7pp | 0.224 |